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  1. danno

    danno New Member

    heres an idea: let's take 53 -100ft garden hoses and hook em together. find 2 miles of relatively flat ground(the flatter the easier) from a center post, run the garden hose 1 mile in 1 direction. drive another post. attach sections of clear tubing to both ends of the hose. fill the hose with water until water line is visible in both clear tubing sections and hold them still against the posts until water settles to a stop. mark the water level mark on both posts. then take the hose and drag it in the opposite direction of the center post to a third post, 1 mile from the center, 2miles from the far post, but in line with the other two. repeat first step of filling with water and making marks. (after 2nd marks are made adjust both 2nd marks equally to match elevation of first marks.)(eg. if on middle post 2nd mark is 10" lower than first mark, raise both 2nd marks 10" to match first marks elevation) now we have 3 marks, all level to the middle post mark... shoot a laser from 1 end mark to the far end mark and then see where it intersects on the middle post relative to the mark thats been made. ( if it drops low of the mark... its round! if it is right on the mark...its flat! and if its high of the mark... its concave!) that's it! it's that simple! ( a high powered spotting scope with horizontal line could be used instead of laser also. or even a really fancy transit with 2mile range) and if you're wondering what good filling a miles worth of garden hose would do... its called a water level (water will always sit level to itself. yes even inside of a hose* so long as no section of the hose is higher than the ends) its how they leveled mobile homes for years and still do. SO... there ya have it! you know youre right! you know they're wrong! stop arguing nonsense and someone put their money where their mouth is please!
     
  2. danno

    danno New Member

    2016-08-04-11-36-30--1793501683. the basic water level concept
     
  3. Mick West

    Mick West Administrator Staff Member

    Someone actually did this a year or so ago, but, as I recall, it was kind of a video of the setup, and not very clear on the results, like it was an initial test. I forgot about it, and can't find the video, but it's probably out there somewhere.
     
  4. Mick West

    Mick West Administrator Staff Member

  5. Z.W. Wolf

    Z.W. Wolf Active Member

    Wouldn't work with a laser. Lasers diverge. You get a cone of light, not a pencil thin line that goes on forever. Lasers are basically spotlights.
     
  6. Mick West

    Mick West Administrator Staff Member

    Camera end
    Metabunk 2018-05-13 21-13-18.

    Middle station at 500m
    Metabunk 2018-05-13 21-14-44.

    End station at 1000m
    Metabunk 2018-05-13 21-16-11.

    The black and white targets are visually aligned in a straight line. The water levels at each end match the targets, the water level in the middle is higher.
    Metabunk 2018-05-13 21-17-35.
     
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  7. Z.W. Wolf

    Z.W. Wolf Active Member

    The video does show the concept that water doesn't really bend. Each column of water points to the center of the Earth.

    If you had a spherical magnet and sprinkled iron fillings on the entire surface, the iron fillings aren't bending.
     
  8. Mick West

    Mick West Administrator Staff Member

    I don't think it shows either of those things. The direction of the columns of water is constrained by the tube — it could actually point at 45° and still get the same results. And how could a liquid bend?

    The experiment shows that the level line of the water is not a straight line. Now this is because the value of gravity is about the same, but in a slightly different direction, at each location. But the experiment does not exactly show that. It's consistent with that. It does disprove the notion that the water heights in water level define a plane. They define a curved surface.
     
  9. Z.W. Wolf

    Z.W. Wolf Active Member

    The video could be used to introduce the idea that water doesn't really bend as if it were a single, solid piece of plastic. Water is a liquid. Each water molecule in the ocean is seeking its local level.

    Better?

    I've been reading the comments. I saw the objection, as I thought I would, that this means nothing because the ground isn't really level. It's as if the water level in a section of vertical tubing would be a foot higher if you put a foot tall box under that section.
     
    Last edited: May 13, 2018
  10. Mick West

    Mick West Administrator Staff Member

    I'm not sure you are introducing an idea that anyone needs. Nobody thinks water bends like a single piece of plastic. It's a liquid.